Poison and antidote

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Paracetamol overdose, its anitdote(s), who qualifies for them and their dosing regimens.

Activated charcoal and N-acetyl-cysteine (precursor for glutathione the antioxidant which is used up). But only if their blood paracetamol levels fulfill the Drug Normogram outlined by Rumack-matthew. Given as an infusion of 300mg over 20 hrs, 150mg\1hr then 50mg\4hrs then 100mg\16hrs.

Poor prognostic factors in paracetamol overdose. (5)

Acidosis, especially ph <7.3

Encephalopathy

Elevated Prothrombin time

Elecated Lactic Acid

The above carry a mortality between 80 and 95%

Benzodiazepine overdose

Flumezanil - bdz receptor antag

Aspirin

Alkalinisation of urine or dialysis if severe acidosis

Opioids

Naloxone

Insulin

Glucose + glucagon + potassium if necessary

Organophosphates

They are non-reversible inhibitors of acetylcholinesterase i.e. too much acetyl choline kickin about.

Pralidoxime, rips the organophosphate off the achase and lets it work normally again, probably need to consider a good dose of atropine too.

Methanol

Ethanol!! both compete for alcoholdehydrogenase and so ethanol slows the breakdown of methanol to formaldehyde

Heavy metals, lead, mercury, gold, arsenic

Dimercaprol. Narrow therapeutic index, competes for the same thiol residues on the sides of amino acids as the heavy metals do.

B-blocker overdose

Atropine then glucagon. Your blocking the sympatheic function so stop the parasymp too and you bring back a level of normality.

Liquid Paraquat

Found in weedkillers and you should look out for farmers and keen gardeners especially. Causes really sore mouth with ulcers and all your organs failing... Catch em quick, ask about weedkiller ingestion and start them on activated charcoal.